1. Field of the Invention
This invention pertains to a cover deployment apparatus for a roll-up tarp assembly. More particularly, this invention pertains to such a cover deployment apparatus which includes means for automatically deploying a tarp.
2. Description of the Prior Art
Roll-up tarp assemblies for open truck boxes for trailers are well known. Copies of such are shown in U.S. Pat. No. 4,505,512 and U.S. Pat. No. 4,302,043 (Reissued on Nov. 27, 1984 as No. Re. 31,746).
As shown in the aforementioned prior art patents, roll-up tarp cover assemblies were provided for elongated open truck boxes. One edge of a tarp is attached to an edge of the truck box opening. The other edge of the tarp is secured to a bar member. As the bar member is rotated about its axis in either a first or second rotational direction, the tarp is either wound onto or unwound from the bar member. Illustrated most clearly in U.S. Pat. No. 4,302,043 (Re. No. 31,746) the tarp is deployed or wound up by means of a hand crank which is used to rotate the tarp supporting bar member. Such a procedure presents undesirable consequences. For example, due to the weight of the tarp, the hand crank operation may be difficult and cumbersome. Also, the crank tool must be separately housed and becomes an item which can be damaged or misplaced.
An additional problem associated with such prior art appratus is presented by use of the tarp supporting mechanisms used in the truck trailors. For example, as shown in the aforementioned U.S. Pat. No. 4,302,043 (No. Re. 31,746) the truck trailer includes a plurality of transverse bows on which the tarp rests when it is deployed. The presence of these bows are an obstacle to loading and unloading of the trailer. Accordingly, it would be desirable to eliminate the need for the bows.